The service requirements of network applications have shifted from high throughput to high media quality, interactivity, and responsiveness, which can be referred to as QoE (Quality of Experience). QoE is thus application-dependent and multidimensional. Although it may not be difficult to measure individual dimensions of the QoE, how to capture users' overall perceptions when they are using different network applications remains an open question. It is particularly difficult to obtain QoE metrics that do not require direct feedback from the user. Querying users about their experiences or directly monitoring is often too intrusive except under non-real world conditions such as in labs or studies where the participants volunteer or are paid to participate. Therefore QoE metric data can be unavailable in many real-world resource usage cases.
While operators today have ways to monitor and support differentiated Quality of Service (QoS), automated methods to translate QoS to QoE for general applications are limited to a few audio or video streaming applications. In other resource usage cases, QoS metrics have not been translated into QoE metrics. As a result, administrators and service providers are not able to manage networks and resources to improve QoE or to offer services that improve or control QoE.